Oastler



(no Model.)

W; G. OASTLER.

ROTARY SCREEN FOR STONE, &0.

No. 255,325. Patented Mar. 21,1882.

Q liwmforx- UNITED STATES PATENT GEEIQE.

\VILLIAW C. OASTLER, OF NEV YORK, N. Y.

ROTARY SCREEN FOR STONE, 84.0.

SPECIFICATION forming part of Letters Patent No. 255,325, dated March 21, 1882,

Application filed June 8, 1881.

To all whom it may concern:

Be it known that I, WILLIAM OIIUncIIILL OASTLER, of the city of New York, in the county and State of New York, have invented certain new and useful Improvements in R0- tary Screens for Stone and other Substances, of which the following is a specification.

The principal object of my invention is to provide a screen for screening stone for roadways which will effectively separate the spalls or thin elongated chips from the pieces which are of approximately uniform dimensions, more nearly resembling the cube in form, and which are used for the wearing-stirface of road ways.

To this end my invention consists in a rotary screen comprising a section or portion in which are elongated holes or slots which are so disposed that their lengths extend in different directions, some having their length parallel with the length of the screen, others having their length transverse to the length of the screen, and still others having their length oblique, so that they extend spirally in the shell or cylindric body of the screen. The slots so disposed are more certain to catch and discharge all long chips and spalls than are slots the lengths of which all extend in one direction.

The invention also consists in a rotary screen comprising a portion or section having elongated holes or slots which are so disposed that their lengths extend in various or different directions, and comprising a second portion or section surrounded or incloscd by an outer shield or casing which is imperl'orate opposite the holes or perforations in said second portion of the screen. If long pieces .enter the holes or openings in the screen, they willstrike against the imperforate part of the shield or casing, and will thus be prevented from passing out said holes or openings, and as said screen is rotated will fall back into the screen and be delivered from the end thereof as unfit for use unless again broken.

In the accompanying drawings, Figure 1 represents a side view, partly in section, of a screen embodying my invention; and Fig. 5 represents a section thereof upon the dotted line 00 m, Fig. 1.

(No model Similar letters of reference designate corresponding parts in both tigurcs.

My improved screen may be attached to any description of crusher, and is supported by a central shaft, A, which rotates in suitable bearings in a frame-work (not here shown) in the ordinary way. The screen here shown comprises three sections or portions, B B B The first section, B,'is covered with wire-gauze or other suitable iinely perforated or reticulated material, and separates from the crushed or broken stone, which enters at that end of the screen, the sertenings, which are often used for binding material in the construction of roadways and for repairs.

From the section B the broken stone passes by gravity into the section B, in which are numerous elongated openings or slots,a, which are too narrow for the passage of pieces of stone which nearly approach the cube in form and are desirable for making the wearing-surface. of a. roadway. The elongated holes or slots a. are intended for the passage of all spalls and long, thin chips; and in order to render said holes or slots more effective they are so disposed that their lengths extend in different directions upon the screen. For example, certain of said holes or slots are disposed so that their lengths are transverse to the length of the screen, certain others are disposed so thattheir lengths are lengthwise of the screen, and still others are disposed so that they extend obliquely or spirally on the screen. This arrangement of the holes or slots is very advantageous, because all the spalls or long, thin chips are then far more likely to be caught by them, and a more thorough and effective separation is produced.

The portion B of the screen, into which the broken stone passes after leaving the portion 13, has numerous round perforations or holes, b, which are of a size to permit the passage of pieces of a proper size. to form the wearingsurlace of a roadway-say about two (2) inches in diameter-and in order to prevent the passage through said holes of long pieces I inclose or surround the portion 13 of the screen by an outer shield or casing, G, which is placed at a sufficient distance from the screen to leave a space of about the size of the holes or per forationssay two (2) inches-between the screen and shield or casing.

The shield or casing is closed at the ends, and is here shown as secured to the screen by knee or angle pieces, 0; but it may be secured in any other suitable way. The shield or casing is here shown as composed of a number of separate pieces extending longitudinally upon the screen and placed at a little distance apart, so as to leave a space between them a little more than equal to the diameter of the holes or perforations Z) and the space between the screen and the shield or casing.

The portions of the screen which come between pieces which form the shield, or oppo' site the spaces between such pieces, are not perforated, and the pieces themselves which form the shield are wholly iin 'ierl'orate; but,

instead of being composed of several pieces, the shield or casing might be composed of one piece and be provided with openings or perforations entirely out of line with the perforations or holes in the screen. In any case the shield or easing should be imperforate opposite the holes or perforations in the screen.

From the above description it will be clear that any pieces which approach nearly to the cube in form may readily pass through the holes or perforations I) in the screen, thence between the screen and the shield or casing, and finally out the spaces between the pieces of which the said shield oreasiug is composed, which I regard as openings in the shield or casin It will also be clear that it any long pieces enter the holes I) they will strike against the shield or casing, which is imperforate opposite such holes, and can get no farther, and hence such pieces will drop back into the screen as the latter rotates.

By my invention I provide a screen which may be substituted for any ordinary rotary screen, and which is much more advantageous for separating stone for roadways than the screens heretofore in use.

Instead of the shield being made of separate sections with longitudinal openings between them, itmay be made of sections ofotherformas, for instance, in the form of bands-the holes Z) I) of the screen being arranged to correspond with and come within the said sections.

The sections or pieces which form the shield may be set somewhat eccentric to theperiphery ot'thescreenthatis,withonelongitudinaledge at a greater distance from the screen than the opposite edgeso as to facilitate the passage of pieces between the screen and shield. This would provide greater freedom of discharge for the spalls and chips and prevent choking.

What I claim as my invention, and desire to secure by Letters Patent, isp l. A rotary screen comprising a section or portion having in its periphery elongated holes or slots (1, some of which extend transversely of the screen, others of which (XtOlltl diagonally or obliquely otthe screen, and still others of which extend longitudinally ot' the screen, substantially as specified.

2. A rotary screen comprising a portion or section having elongated holes or slots which are so disposed that their lengths extend in various or diti'erent directions, and comprising a second portion surrounded or inclosed by an outer shield or casing which is iinperforate opposite the holes or perforations in said second portion of the screen, substantially as specitied.

W. (J. OASTLER. Witnesses:

FREDK. HAYNES, ED GLA'IZMAYER. 

